Facebook could face an Australian class action, and a former soldier is leading the charge

Facebook has apologised for the Cambridge Analytica data scandal, which affected at least 87 million users

ABC News: Nic MacBean

The man leading a legal challenge against Facebook in Australia says he hopes the case will encourage people to be more careful with what they share on social media networks.

Edward Poljak, a printer and self-described astronomy researcher, was recently notified that his data may have been breached in its Cambridge Analytica data scandal.

The former soldier told The Law Report he had put strict privacy settings on his profile out of respect for the privacy of his friends, some of whom worked in law enforcement and were former members of the military.

He was concerned the data breach could put their jobs or safety at risk.

"I was shocked, and a little bit angry because it was like someone had stolen our data ... we didn't know what the implications could be until it started hitting the news," Mr Poljak said.

He later learned his data may have been leaked because one of his friends had taken a personality quiz on Facebook, called This Is Your Digital Life.

"It's time to assess how we do use these online social media platforms and be very careful of what we post and share," he said.

People who took the quiz handed over not only their data but also information from the profiles of their friends on the social network.

Cambridge Analytica then bought this data from the app developers behind the quiz. The firm is currently being investigated in the United States over allegations it used the data to influence the last presidential election.

There are reportedly a number of lawsuits against Facebook and Cambridge Analytica over the scandal.

Mr Poljak said businesses should be held accountable for their actions.

"[It will be worth it] if it brings awareness to everybody and opens up doors for people to be careful on social media, that our data is not safe," he said.

A spokeswoman for Facebook declined an interview with The Law Report. She also declined to respond to questions on the current lawsuits against Facebook and on its approach to tougher privacy reforms worldwide.

But she said in an emailed statement: "We are fully co-operating with the investigation currently underway by the Australian Privacy Commissioner and will review any additional evidence that is made available when the UK Office of the Information Commissioner releases their report."

According to IMF Bentham, the law firm funding the legal challenge, the group complaint asks Acting Privacy Commissioner Angelene Falk to determine that Facebook interfered with the users' privacy, that the company should pay compensation to the affected Australian users and that it makes moves to prevent future data breaches.

The complaint also asks for Facebook to apologise to its affected Australian users.

Case could be a 'game-changer' for privacy law

If successful, the Privacy Commissioner could order that Facebook pay a certain amount of money to the users covered by the complaint, which can then be enforced in a formal class action in the Federal Court.

The law firm declined to say how many people have joined the class action to date.

Mr Poljak said he still used Facebook, but had culled his friends list to close friends and family, and no longer revealed details of his location online.

"I actually wanted to stop using it altogether and close it all off but it harms my social [life] and my status with my family and my friends to keep in contact with them so ... what do I do?"

He was not expecting a great deal of compensation from the legal challenge, but said he would donate anything he received from it to charity.

Norton Rose Fulbright special counsel Jim Lennon, who specialises in data breaches and cyber security, said the case was a "game-changer" for privacy law, at a time when large data breaches were increasingly common.

While Facebook would vigorously defend itself against the legal challenge, Mr Lennon said that if the users won, he expected more lawsuits to be launched over data breaches in future.

"It's bad for business in a sense that all of a sudden privacy breaches... [are] going to sound in very distinctly public and financial consequences, at least more often," Mr Lennon said.

"But what will be good for the community is that corporate Australia and the Commonwealth government agencies also covered by the Privacy Act, I think, will now take privacy even more seriously than they have.

"And many are doing the right thing. But I think now people will not regard privacy as a nice to have in respect of compliance.

"They will resource it properly and really understand that this is a human right of their customer base… and protect the information properly."